I have a hosting account set up with 8 available databases in PostgreSQL and another 8 in MySQL. I have now used all 8 mySQL databases on various projects. I now need another database. My two options are to use a PostgreSQL database or just add more tables to one of the mysql databases. I'm a little wary of using the PostgreSQL databases because i have lots of existing code that uses mysql connect and result functions in php. I don't want to have to rewrite it nor do I know how to connect to a PostgreSQL database? Any ideas on what I should do?
PHP hooks up to PostGreSQL as easily as it does to MySQL. Almost all of your queries will probably work as well. You could also ask your host to enable more databases. It's a silly artificial limit anyway, if you have any sort of 'relationship' with them besides just paying the bills on time, they should be able to bump that up for you.
If you're using a database abstraction layer such as MDB2 then switching to Postgres should be easy. If you're not - now seems a good time to start